Re: [PATCH 3/8] platform: x86: dell-laptop: no need to check return value of debugfs_create functions

["Pali Rohár" <pali.rohar@gmail.com>]

On Wednesday 12 June 2019 14:12:53 Greg Kroah-Hartman wrote:
> When calling debugfs functions, there is no need to ever check the
> return value.  The function can work or not, but the code logic should
> never do something different based on this.
> 
> Cc: Matthew Garrett <mjg59@srcf.ucam.org>
> Cc: "Pali Rohár" <pali.rohar@gmail.com>
> Cc: Darren Hart <dvhart@infradead.org>
> Cc: Andy Shevchenko <andy@infradead.org>
> Cc: platform-driver-x86@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/platform/x86/dell-laptop.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
> index a561f653cf13..94a2f259031c 100644
> --- a/drivers/platform/x86/dell-laptop.c
> +++ b/drivers/platform/x86/dell-laptop.c
> @@ -2176,9 +2176,8 @@ static int __init dell_init(void)
>  	kbd_led_init(&platform_device->dev);
>  
>  	dell_laptop_dir = debugfs_create_dir("dell_laptop", NULL);
> -	if (dell_laptop_dir != NULL)
> -		debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
> -				    &dell_debugfs_fops);
> +	debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
> +			    &dell_debugfs_fops);

Hi!

So... debugfs_create_dir() can return NULL, right?

And it is then OK to call
debugfs_create_file("rfkill", 0444, dell_laptop_dir, ...) with
dell_laptop_dir = NULL?

Where would be that "rfkill" file created?

>  
>  	dell_laptop_register_notifier(&dell_laptop_notifier);
>  

-- 
Pali Rohár
pali.rohar@gmail.com